5-HT2A/5-HT2C inverse agonist 1 is a potent and dual 5-HT2A and 5-HT2C receptor inverse agonist with a hERG inhibitions, thus avoiding cardiovascular risks. 5-HT2A/5-HT2C inverse agonist 1 shows significant antipsychotic efficacy in the MK-801 -induced mouse model. 5-HT2A/5-HT2C inverse agonist 1 is promising for research of psychosis.